K-Pop fans might be familiar with Otani Ryohei (Roommates, Cool Kiz on the Block) - he's part of the main leads in this drama.
So the closing credits of Japanese drama I Got Married As a Job (starrting Aragaki Yui, Hoshino Gen, Otani Ryohei) has the main characters dancing to this song. The drama was a hit and the dance has become a craze to the point that even the US Embassy in Tokyo had to do their own version.
The song is Koi by Hoshino Gen so the dance is called Koi Dance 恋ダンス
Here's the original from the drama
Covers of it went viral (up to millions of views)
This cover has 15 million views
Here is the US Embassy in Tokyo doing their own take